Rapid curing resin compositions comprising a phenol-aldehyde condensation polymer modified with an acyl hydrazide

ABSTRACT

Described herein are resin products having particular utility as rapid curing adhesives for wood and other materials, and processes fo making the resin compositions. These products are made by reacting an aldehyde condensation polymer containing reactive alkylol groups, such as a phenol-formaldehyde condensation polymer, with an acyl hydrazide. When the resulting acyl hydrazide-modified polymers are blended with an appropriate curing agent, such as an aldehyde, the compositions cure very rapidly at ambient temperatures. When pieces of wood or other materials are spread with the preferred resin compositions of this invention and brought into contact with another wood surface the bond strength develops within minutes. The durability, strength and flexibility of the adhesives of this invention under adverse weathering conditions are excellent.

United States Patent [191 Tiedeman 1 RAPID CURING RESIN COMPOSITIONS COMPRISING A PI-IENOL-ALDEHYDE CONDENSATION POLYMER MODIFIED WITH AN ACYL HYDRAZIDE [75] Inventor: George T. Tledeman, Seattle, Wash.

[73] Assignee: Weyerhaeuser Company, Tacoma,

Wash.

[22] Filed: May 25, 1971 [21] Appl. No.: 146,784

[52] US. Cl 260/59, 161/205, 161/215, 161/257, 161/262, 260/29.3, 260/33.4 R, 260/5l.5, 260/64, 260/67.6 R, 260/70 R, 260/831 [51] Int. Cl C08g 5/18, C08g 9/04 [58] Field of Search 260/51.5, 59

[56] References Cited UNITED STATES PATENTS 3,364,179 1/1968 Kirkpatrick 260/51.5 3,376,262 4/1968 Pasky 260/59 3,377,317 4/1968 I-Ioxie 260/59 3,398,122 8/1968 Shephard et a1.... 260/59 X 3,436,373 4/1969 Cox et a1, 260/51.5 3,444,137 5/1969 Higginbottom 260/5l.5 3,459,708 8/1969 Stevens 260/59 3,461,099 8/1969 Muzyczko et a1... 260/59 3,487,046 12/1969 Negrevergive 260/5l.5 3,509,096 4/1970 Sobel 260/51.5 3,546,172 12/1970 Johnson et a1.. 260/51.5 3,558,559 1/1971 LeBlanc 260/51.5 3,558,560 1/1971 Huck et a1. 260/59 3,563,952 2/1971 Schmoll 260/59 3,678,103 7/1972 l-luck 260/51.5 3,275,605 9/1966 Eastes et a1 260/51.5

[451 Aug. 28, 1973 FOREIGN PATENTS OR APPLICATIONS 615,335 l/l949 Great Britain OTHER PUBLICATIONS Modern Plastics Encyclopedia, 1968, pp. 9, 13 141-144, 183-184 Primary Examiner-Howard E. Schain AttorneyChristensen & Sanbom [57] ABSTRACT Described herein are resin products having particular utility as rapid curing adhesives for wood and other materials, and processes fo making the resin compositions. These products are made by reacting an aldehyde condensation polymer containing reactive alkylol groups, such as a phenol-formaldehyde condensation polymer, with an acyl hydrazide. When the resulting acyl hydrazide-modified polymers are blended with an appropriate curing agent, such as an aldehyde, the compositions cure very rapidly at ambient temperatures. When pieces of wood or other materials are spread with the preferred resin compositions of this invention and brought into contact with another wood surface the bond strength develops within minutes. The durability, strength and flexibility of the adhesives of this invention under adverse weathering conditions are excellent.

46 Claims, No Drawings RAPID CURING RESIN COMPOSITIONS COMPRISING A PIIENOL-ALDEHYDE CONDENSATION POLYMER MODIFIED WITH AN ACYL I-IYDRAZIDE BACKGROUND OF THE INVENTION This invention relates to the preparation of rapid curing resin compositions, to the resin compositions per se, and to the use of these resin compositions as adhesives.

For many years the adhesives used to bond wood together to make plywood, laminated beams, furniture, etc., have employed aldehyde condensation polymers of phenol, urea, resorcinol, etc., such as phenolformaldehyde resins, resorcinol-formaldehyde resins, phenol-resorcinol-formaldehyde resins, ureaformaldehyde resins, and others. Although each of these resins have advantageous characteristics, they all have relatively slow curing rates.

The slow cure rate of these resins has necessitated long press times with concurrent restriction on production when used in the manufacture of laminated beams and plywood and in other construction uses. To overcome the slow cure rates, many modifications of the above resins have been proposed. Other resins such as the epoxies have been proposed, but their expense and certain of their physical properties have limited their use. The adhesives of this invention employ aldehyde condensation polymers modified with particular acyl hydrazides. These resins not only have rapid cure rates but develop adequate adhesive bond strengths in a short amount of time at ambient temperature, thereby eliminating the need for long press times and application of heat to develop sufficient bond strength.

In U. S. Pat. No. 2,509,183, Auten describes thermosetting resins which are condensation products of an aldehyde, an alcohol and a particular group of symmetrical aliphatic dihydrazides. Some of the products are suggested as plywood adhesives, but the resins do not have the fast curing characteristics of the products of this invention.

SUMMARY OF THE INVENTION This invention is directed to acyl hydrazide-modified aldehyde condensation polymers, to rapid curing resin compositions useful as adhesives, and to processes for the preparation thereof.

This invention is also directed to a method of bonding a plurality of members one to the other comprising applying to a surface of a first member a first component comprising an acyl hydrazide-modified polymer of this invention, applying to a surface of a second member a second component comprising a curing agent in an amount sufficient to cause said first component to become infusible, and assembling the first and second members so that the first and second components are brought into intimate reacting contact.

The acyl-hydrazide modified polymers of this invention are prepared by reacting together an aldehyde condensation polymer containing reactive alkylol groups and an acyl hydrazide containing at least two aldehyde-reactive sites located on amino, hydrazino and/or acyl hydrazido groups. A preferred class of such acyl hydrazides are those of Formula I set forth hereinafter.

The rapid curing resin compositions of this invention are prepared by blending a curing agent with the acyl hydrazide-modified polymer. The resin compositions rapidly set to an insoluble, infusible condition at ambient temperatures. Optionally, heat may be applied to further increase cure speed. The resins can be used to bond wood to wood, metal to metal, wood to metal, fabric, and many other materials where durable, moisture-resistant, heat-resistant adhesive compositions are needed.

DETAILED DESCRIPTION OF THE INVENTION Many of the aldehyde condensation polymers of phenol, resorcinol, urea, and melamine having reactive alkylol groups have been widely used as adhesives and their properties are well known. Polymers, as used herein, refers to resinous mixtures that do not crystallize or have a sharp melting point. Reactive alkylol groups are alkylol groups capable of reacting with the acyl hydrazides used in this invention to modify the aldehyde condensation polymers. Condensation is used herein to mean a polymerization reaction in which a molecule, such as water, is eliminated and is to be distinguished from addition in which no by-product is formed. Further, the aldehyde condensation polymers used in this invention exclude those having dominant amide forming substituents.

Three classes of polymers are preferred: phenoplasts, aminoplasts, and ketone-aldehyde condensation polymers. They include such resins as the acid or base catalyzed phenol-aldehyde resins, urea-aldehyde resins, melamine-aldehyde resins and acetone-aldehyde resins. The following references disclose methods of preparing the condensation resins useful in this invention: The Chemistry of Synthetic Resins by Carleton Ellis, Reinhold Publishing Co., 1935; Phenolic Resin Chemistry by N. J. L. Megson, Academic Press Inc., New York, 1958; Aminoplasts by C. P. Vale, Cleaver- Hume Press, Ltd., London, England; and British Patent 480,316.

Specifically, the aldehyde condensation polymers which can be used include (I) phenoplasts comprising the condensation polymers of an aldehyde such as formaldehyde with a phenolic type material having at least two positions ortho and/or para to the hydroxyl group open for reaction such as phenol, phenolresorcinol, xylenol, cresol, resorcinol, and their derivatives, (2) aminoplasts comprising the condensation polymers of an aldehyde such as formaldehyde with compounds such as benzoguanamine, dicyandiamide, urea, melamine-urea, melamine, and their derivatives, and (3) ketone-aldehyde condensation polymers such as acetone-formaldehyde, methyl ethyl ketone formaldehyde, methyl isobutyl ketone formaldehyde, and the like. The preferred resins are water-soluble, liquid, thermosetting phenol-aldehyde resins.

A preferred resin is an ortho-condensed phenolformaldehyde resin made by condensing 0.7 to 1.0 moles formaldehyde with 1 mole phenol in the presence of an ortho-directing catalyst such as calcium acetate. Such resins are known. Each of the aldehyde condensation polymers mentioned above is prepared and kept under conditions which prevent it from condensing to an infusible state by known methods. Although phenol is the preferred reactant, the phenolic resins may be modified by incorporating into them predetermined amounts of other monohydric phenols or dihydric phenols such as resorcinol, or other polyhydroxy aromatic compounds.

Exemplary of the aldehydes which can be used in preparation of the condensation polymer are formaldehyde, paraformaldehyde, polyoxymethylene, trioxane, acrolein, and aliphatic or cyclic aldehydes such as glyoxal, acetaldehyde, propionaldehyde, butyraldehyde, and furfuraldehyde. Condensation, when using formaldehyde, furfuraldehyde, paraformaldehyde, polyoxymethylene or trioxane, is generally accomplished with the use of a mildly acid or alkaline catalyst or in the absence of a catalyst. When using acrolein, glyoxal, acetaldehyde, propionaldehyde or butyraldehyde, condensation is generally accomplished by combining the reactants in the presence of a strongly acid catalyst, neutralizing the reaction product, adding more aldehyde, and further reacting in the presence of a mildly acid, or alkaline, catalyst.

In accordance with this invention, the aldehyde condensation polymers containing reactive alkylol groups are modified by reaction with an acyl hydrazide containing at least two aldehyde-reactive functional groups, one of which is a carbohydrazide group and the second of which is an amino, hydrazino or carbohydrazide group. It is very desirable, in order to produce the low-temperature fast curing products of this invention, to first produce the aldehyde condensation polymer and then subsequently modify that polymer by reaction with the acyl hydrazide. Simultaneous reaction of all the reactants, e.g., phenol, formaldehyde and acyl hydrazide, generally produces an inferior, heterogeneous mass, e.g., comprising essentially a hydrazideformaldehyde condensation polymer containing free phenol.

Exemplary of the class of acyl hydrazides useful in this invention are those of the formula:

wherein a and b are integers of from to 8 and the sum ofa and b is from 0 to l2;x isO or 1; R is CH=CH,

( JONaH;

47 0 NgHr and R is NHZ, -N,H, or

A preferred class of acyl hydrazides are those of the formula:

Wherein R is -Nii,, N,1-r, or

R NzHl;

and R is CH=CH-,

phenylene, biphenylene, naphthylene or (Cl-l where c is an integer of from 0 to 8. Especially preferred are carbohydrazide, glutaric dihydrazide, adipic dihydrazide, sebacic dihydrazide and p-aminobenzoylhydrazide. Exemplary of other acyl hydrazides useful in this invention are oxalyl dihydrazide, malonic dihydrazide, succinic dihydrazide, azelaic dihydrazide, thiodipropionohydrazide, maleic dihydrazide, fumaric dihydrazide, itaconic dihydrazide, citric trihydrazide, terphthaloyl dihydrazide, 2,fi-naphthalenedicarbohydrazide, 4,4'-biphenyl dicarbohydrazide, 2,2'-biphenyl dicarbohydrazide, o-amino-benzoylhydrazide, m-aminobenzoylhydrazide and glycine hydrazide.

Acyl hydrazides having the basic structure of Formula l, but further substituted with non-interfering substituents, are also useful in this invention. By noninterfering substituents" is meant those substituents which do not detract from the usefulness of the acyl hydrazide in this invention. For example, hydroxyl, ether, alkyl, aryl, cyano, sulfide, and mercaptan groups are non-interfering substituents which could be attached to the carbon chain of the acyl hydrazides of Formula 1 without reducing their usefulness, i.e., without significantly changing resin shelf life or adhesive cure speed. An acyl hydrazide containing such a non-interfering substituent which is found to be satisfactory for purposes of this invention is 3-methylazelaic dihydrazide.

Also useful for purposes of this invention are the acid salts of the acyl hydrazides of formula I, which salts are formed by the reaction of such hydrazides with nonoxidizing acids such as the hydrohalide acids, sulphuric acid, phosphoric acid, acetic acid, propionic acid, butyric acid, and the like. These salts are equivalent, for purposes of this invention, to the free acyl hydrazides, and will normally be present in the reaction system when the aldehyde condensation polymer is reacted with the acyl hydrazide under acidic conditions.

The amount of hydrazide reacted with the condensation polymer generally ranges from about 0.05 to 2.0 parts, preferably 0.1 to 1.0 parts, by weight of the hydrazide to each part of the condensation polymer. More than 2.0 parts by weight of the hydrazide to each part of polymer can be used but there is usually little advantage in doing so. Most of the hydrazides disclosed react with the aldehyde condensation polymers at room temperature, but to insure complete reaction the mixtures are usually heated to reflux. Many of these reactions are exothermic in nature and cooling is required to control the reaction. This exothermic nature of the reaction is in some instances controlled by slow addition of the hydrazide to the prepared polymer. It may be desirable under some circumstances, however, to add the polymer to a solution of the acyl hydrazide.

The hydrazide-modified aldehyde condensation polymers make up the first component of the resin composition of this invention. The first component is prepared so as to have a relatively long storage life so it can be shipped and stored. for fairly long periods of time without gelation. Various of the hydrazide-modified polymers can be stored for periods exceeding several months without adverse effect on their performance.

The second component of the resin composition is a curing agent which can be, for example, an alkylene donating compound, a diisocyanate, an epoxide, or an epoxide-aldehyde mixture, used either alone or in admixture with conventional thickening agents. Other materials that readily donate alkylene bridges to the polymer system are also generally suitable. The resin the surfaces are brought into contact the first and second components react forming an infusible glue line between the materials. If desired, other ingredients can be added to the resin compositions. Such ingredients ll ll HsNzC CNzHa compositions are prepared immediately prior to use by 5 include conventional fillers, pigments, plasticizers, and blending together the hydrazide-modified aldehyde the like in amounts ordinarily employed for such purcondensation polymer and the curing agent. Reaction poses. The resin compositions of this invention do not takes place at ambient temperature and the blended need additional catalyst or heat to cure them. They are mixture gels rapidly to an insoluble, infusible state. The curable at ambient temperatures, most of them in very preferred resin compositions of this invention set to an 10 short time periods after mixing of the two components. insoluble, infusible state within a few minutes. lnsolu- Additionally the resin compositions develop bond ble is intended to mean not soluble in common solstrengths sufficient to hold articles together in a relavents such as water, alcohols, ketones, hydrocarbons, tively short amount of time. esters, glycols, and the like. Optionally, heat may be ap- The following examples are provided by way of illusplied to the curing composition if desired to further detration only and are not intended to be limiting of the crease the required cure time. Sufficient curing agent invention. All parts and percentages are by weight unis added to the first component to form an insoluble, less otherwise indicated. infusible product. The amount of curing agent is not critical and may range, for example, from 0.05 to 2.0 parts by weight per part of hydrazide-modified conden- EXAMPLE I sation polymer. This example illustrates the fast cure rates of the Although the reaction mechanism involved in the resin compositions of this invention. Cure rate is deterpreparation of the resin compositions of this invention mined by means of gel time. Gel time is determined is not specifically known, it is believed that when an alby weighing out a lO-gm. aliquots of the first compodehyde is used as the curing agent, it reacts predominent, adjusting the pH's to the desired points, and mixnantly with the amino, hydrazino and/or carbohydraing the second component with the first component. zide groups in the hydrazide-modified polymer. The time elapsed from mixing to gelling of the compo- The preferred curing agent is an aldehyde such as iti n iS t rmed gel time. formaldehyde, though the formaldehyde-forming com- A high-solids predominately ortho condensed phepounds polyoxymethylene, trioxane and paraformaldenol-formaldehyde polymer is prepared by mixing 43.06 hyde are also quite satisfactory. Other aldehydes may parts by ght p enol, 451 parts Water, 1135 parts he also used, for example, aliphatic or cyclic aldehydes flake paraformaldehyde and Part5 Calcium having from 1 to 8 carbon atoms such as acrolein, acetate monohydrate. The mixture is brought to reflux glyoxal, acetaldehyde, proprionaldehyde, butyralde- (approximately 109C.) in about 60 minutes at a unihyde, and furfuraldehyde. Phenolic resoles and other f rate and h ld at rcflllX f r 120 minutes. To Sepasimilar polymers having free methylol groups are also rate IOO-gram aliguots of this prepolymer are added efficient curing agents. Suitable isocyanate curing 0.305 gram moles of each of the acyl hydrazides listed agents include toluene diisocyanate, phenylene diisocyin Table 1. Each of the resulting mixtures is refluxed for anate, 1,6-diisocyanatohexane, and the like. Suitable 2.25 hours and cooled, and then 26.3 grams of methaepoxy curing agents for use alone or in admixture with nol is stirred into each mixture. The methanol serves to an aldehyde include diglycidyl ether of disphenol A, stabilize the hydrazide-modified polymers and prevent epoxidized phenolic novolacs, epoxidized polyglycols any separation of water. IO-Gram aliquots of each of and the like. the resulting hydrazide-modified polymers are then When bonding materials together, the hydrazideweighed out, the pHs are adjusted to the desired valmodified polymer and curing agent are kept separate ues, and 2.5 ml. of a solution comprising 55 parts by until needed. Typically, they are then intimately mixed weight formaldehyde in 35 parts methanol and 10 parts together and the resulting rapid curing resin composiwater is added to each aliquot. The mixtures are stirred tion of this invention is promptly spread on the materirapidly until gelled and the times are recorded. The soals to be bonded by any conventional means. An autolution pH has some effect on the gel time of the resins. matic mixing-dispensing gun is most useful in this re- For most hydrazide-modified polymers the gel time degard. Certain of the resin compositions of this invention creases as the pH is lowered from about 8 to about 2. have such rapid cure times that they begin to cure be- In general, variations in pH above 8 have little effect on fore they can be spread on the material to be bonded. gel times. The pH effect is dependent primarily on the In such cases, the first component can be spread on one particular acyl hydrazide employed, but it is also desurface of the material to be bonded and the second pendent on the solvent used and on the concentration component spread on the second surface to be bonded. of hydrazide in the modified polymer. Table 1 lists the Such a process is described in U. S. Pat. No. 2,557,826 hydrazides used and their structures, and the pH ranges using phenol-resorcinol-formaldehyde resins. When over which similar gel times were observed.

TABLE 1 pH Hydrazide Structure Gel, time Range Carbohydrazide O l50 seconds 2.8-7.6

fi Nz NzHg Oxalyl dihydrazlde O O 2. 2-5. 6

seconds Hydrazide Structure Gel, time Ra ga Malonic dihydrazldo 75-95 seconds 3. -7. 1

H Nfl l C HglNzH;

Succinie dlhydrazide 100 seconds 3. J-7. 8

HgNzKCHzhlNzHa Glutaric dihydrezlde O 100 seconds 24 8-7. 5

2C 3(C 2)a N2 Azelaic dihydrazide 85-105 seconds 3. 3-6. 7

H3Nz (CH2)7( %NgH3 Sebacic dihydrazide O 44 seconds-6 hours 3. 8-10. 1

IhNgt 0 Hz) a NzHs Thlodiproprlohydrazldo 0 -85 seconds 2. 8-6. 9

(HaNzll CHzCIIzhS Malclc dihydrazidc 0 ON 211:. -65 seconds 3. 8-7. 2

0 ON 2H:

Fumaric dihydrazlde 0 30-47 seconds 3. 8-7. 4

(lNzH (JNzHa Itacom'c dihydrazide 480-780 seconds 3. 3-7. 8

C H2=C lNzHs H 0 CNzH; ll

Citric trihydrazide H2O C ONzHs 30-40 seconds--. 3. 1-5. 8

HO-C C ONzHs H23] C ONzHs Te rphthaloyl dihydrazide O O Gelled during preparation HaN2 C NzH3 2,fi-Nuphthalenedlcarbohydrazlden C ONZH: 7 minutes 5. 7

HgNzO C 4,4-Biphenyl dicarbohydrazide O Gelled during preparation HaNz -1 2,2'-Bipheny1 dicarbohydrazide" 0 24 hours 0. 6-6. 6

NzHg o-Aminobenzoylhydrazide v /NH; 73-502 seconds 3. 5-10. 5

O NzHs m-Arninobenzoyl hydrazide 1TH: seconds 6. 2

O NzHs p-Aminobenzoylhydrazide O 10O seconds 2. 0-6. 8

N Hg-Q- NzH:

Gelation of the modified polymer during preparation indicates that the phenol-formaldehyde polymer and acyl hydrazide do react and that, using appropriate concentrations and reaction conditions, a suitable modified prepolymer can be obtained.

EXAMPLE 2 fluxed for 2.25 hours and cooled. Then 26.3 grams of methanol is stirred into each of the resulting hydrazidemodified phenol-formaldehyde polymers.

b. Ten-gram aliquots of each of the modified phenolformaldehyde polymers prepared as described above and weighed out. To selected aliquots there is added an amount of concentrated HCl as indicated in Table 2 below. grams of one of three curing agents, as indicated in Table 2, are then added to each aliquot. The curing agents are:

A. a mixture of 49.08 parts of a solution consisting of 55 parts formaldehyde in 35 parts methanol and parts water, 1.84 parts of a powdered, refined chrysotile asbestos (R.G. 244 asbestos a product of Union Carbide Corp.), and 49.08 of an epoxidized phenolformaldehyde novolac resin having an average of 2.2 epoxy groups per molecule (D.E.N. 431 a product of Dow Chemical C0.);

B. a mixture of 96.39 parts and 3.61 parts of the above-mentioned formaldehyde-methanol-water solution and asbestos, respectively; and

C. 49.08 parts and 1.84 parts of the formaldehydemethanol-water solution and asbestos, respectively, and 49.08 parts of a diglycidyl ether of propylene glycol having an epoxy equivalent of 364 to 380 and a viscosity of 25,000 to 45,000 cps. at C. (D.E.R. 741 a product of Dow Chemical Co.).

After the addition of the curing agent, each aliquot is stirred rapidly and a sample is promptly removed and used in a standard cross lap test. (See Marra, A., Geometry as an Independent Variable in Adhesive Joint Studies, Forest Products Journal, Vol. XII, No. 2, pp. 81-90, 1962.) Stirring of the remaining portion of each aliquot is continued until gelling has occurred. Gel times are recorded in Table 2.

The cross-lap test is conducted by spreading the sample on the central area of a piece of Douglas fir wood 1 inch wide by approximately 34 inch thick and 234 inches long. A similar piece of Douglas fir wood is immediately laid over the first with the grain direction at right angles. A measured quantity of adhesive may be used or an excess may be applied with the surplus resin allowed to squeeze out of the joint. The latter method has been used for the examples given here. As soon as the cross-lap is laid on the first piece, a pressure of pounds is applied for the desired length of time at ambient temperatures. The joint is then broken in tension, the bond strength being recorded in Table 2.

Nromally, wood failure begins to occur at a value of about 150 psi. For many purposes, however, a bond strength well below this value is wholly satisfactory. It should also be noted that strength usually continues to increase significantly for at least a 24-hour period after initial assembly.

TABLE 2 O m. Gel press tensile Acyl curing Hcl/ Time time Break hydrazide agent 10 gm (Seq) (min.) (psi) carbo A Pmyme' 10s 12 200 hydrazide A l .4 105 6 A 2.0 1 5 6 2 1 5 B 65 1 2 2 1 O B 4 20 6 65 oxalyl A 12 3 5 dihydrazide B 40 12 20 rnalonic A A 100 12 124 hydrazide B 40 12 71 succinic A 70 8 75 h drazide B 50 8 l5 gutaric A 50 4 65 hydrazide B 40 4 (3 60 6 275 adipic A 200 10 dihydrazide B 360 10 45 C 390 10 25 azelaic A 180 12 138 hydrazide B 60 12 64 sebacic A 70 12 hydrazide B 420 12 45 Thiodipropionohydrazide A 180 12 90 B 200 12 73 maleic hydrazide A 0.5 12 139 B 0.5 35 12 50 fumaric hydrazide A 0.5 65 12 132 B 0.5 25 12 45 ltaconic hydrazide A 300 12 92 B 30 12 42 Citric hydrazide A 1.0 35 12 101 1.0 17 12 50 isophthaloyl Dihy'drazide A 120 12 102 B 75 12 132 o-Amino' benzoylhydrazide A 115 12 B 55 12 90 m-Amino benzoyl hydrazide B 35 I2 25 p-Aminobenzoylhydrazide A 90 6 45 A 90 12 305 B 50 10 115 C 90 8 110 glycine hydrazide A 30 12 125 B 10 12 40 ethane tricarbohydrazide A 12 162 B 162 12 89 EXAMPLE 3 A series of hydrazide-modified urea-formaldehyde polymers are prepared by mixing together three parts of a urea-formaldehyde resin (Amres 255 a product of Pacific Resins and Chemicals, Inc.), one part of an acyl hydrazide listed in Table 3 below, and 10 parts of N,N-dimethylformamide (DMF). The samples are warmed and stirred until homogeneous. Where DMF was not needed to dissolve the mixture of polymer and hydrazide, it was omitted as indicated in Table 3. Amres 255 is typical of many general purpose ureaformaldehyde adhesive resins readily available on the market. It is made with an approximate 2 to 1 mole ratio of formaldehyde to urea and is cooked to a Gardner viscosity of U at pH of 8.0 and contains 65% resin solids in a water solution.

Part (b) of Example 2 is repeated substituting for the modified phenol-formaldehyde polymers the modified urea-formaldehyde polymers prepared as described above. The gel times observed and the results of the cross-lap tests are shown in Table 3.

TABLE 3 Gm. 11C]; Gel- Press Tensile Curing 10 gm. time, time, brook, Acyl hydrnzide DMF agent polymer 500. min. P .s.i. carbohydmide $323; :1: Ii 55. l3 i5 362 No. A 0. 4 120 12 205 Glutanc dihydrazide No B 0A 80 12 375 N0 C 0.2 12 85 No A 160 12 130 Adipic dihydrazide No B 155 12 135 No C 130 12 130 EXAMPLE 4 Into each aliquot is then stirred 2.5 gm. of a curing A series of hydrazide-modified melamine-ureaformaldehyde polymers are prepared by mixing together three parts of a melamine-urea-formaldehyde resin (Melurac 400 a product of American Cyanamid Company), one part of an acyl hydrazide listed in Table 4, and 20 parts of N,N-dimethylformamide (DMF). The samples were warmed and stirred. until homogeneous. Melurac 400 is a 100% solids, spray-dried adhesive resin typical of many similar products commercially available which are intended for hot press or radio frequency bonding of wood products. Resins of this type are described in British Patent 480,316.

Part (b) of Example 2 is then repeated substituting for the modified phenol-formaldehyde polymers the modified melamine-urea-formaldehyde polymers prepared as described above. The gel times observed and the results of the cross-lap tests are shown in Table 4.

TABLE 4 Gel- Press Tensile curing gm HCI/ Time Time Break. Acyl hydrazide Agent gm (sec.) (min.) (P.S.T.)

Polymer carbohydrazide A 0.67 45 l2 100 B 12 5 glutaric Dihydrazide A 0.4 12 15 C 0.4 I2 30 adipic Dihydrazide A 0.6 I2 25 B 0.6 I00 12 35 EXAMPLE 5 An acetone-formaldehyde polymer containing about 2% of free formaldehyde is prepared by charging 17746 gm. of 50% formalin, 1270 gm. water and 4173 gm. of acetone into a S-gallon reactor. The temperature of the mixture is adjusted to 40C. and 45.4 gm. of 49.5% sodium hydroxide is added with agitation. The mix is further cooled to 30C. and a second 45.4 grn. portion of 49.5% sodium hydroxide is added. The temperature is then allowed to rise uniformly to 65C. over the next hour using cooling as required to control the exotherm. After reaching the maximum temperature the mixture is held at 6570C. for an additional minutes until the exotherm has completely subsided.

Three parts of the acetone-formaldehyde resin and one part of either sebacic dihydrazide or glutaric dihydrazide are mixed together and warmed on a steam bath for one-half hour. Ten gram aliquots of each of the resulting hydrazide-modified polymers are adjusted to the pHs indicated in Table 5 using concentrated HC].

agent consisting of a solution 55 parts formaldehyde in 35 parts methanol and 10 parts water. Gel times and tensile break strengths determined as in Example 2 are recorded in Table 5.

TABLE 5 Gel Press time Time Tensil Break Acyl hydrazide pH (sec.) (min.) (P.S.l.) glutaric Dihydrazide 6.0 270 4.0 120 12 40 2.4 30 sebacic Dihydrazide 6.7 30 min.

EXAMPLE 6 To gm. of a phenol-formaldehyde polymer prepared as described in Example 1 is added 0.305 moles of glutaric dihydrazide. The resulting mixture is refluxed for 2.25 hours and then cooled. 26.3 Grams of methanol is stirred into the resulting modified polymer.

To 5.0 parts of this modified polymer is added 1.48 parts of toluene diisocyanate. The mixture gels after 30 seconds of rapid stirring.

What is claimed is:

1. An acyl hydrazide-modified condensation polymer comprising the reaction product of a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula wherein a and b are integers of from 0 to 8 and the sum ofa and b is from 0 to 12-,x is 0 or 1; R is CH=CH,

O, S-, phenylene, biphenylene, naphthylene,

OH H --(1 or AJ- )ONzH; ONQHB and R is NH N H or said reaction product being further reactable with a curing agent to form an insoluble, infusible polymer.

2. The modified polymer of claim 1 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

3. The modified polymer of claim 1 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

4. The modified polymer of claim 3 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

5. The modified polymer of claim 1 wherein said phenoplast comprises phenol condensed with formaldehyde.

6. The modified polymer of claim 5 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

7. The modified polymer of claim 1 wherein said acyl hydrazide is selected from those of the formula iiT zHK;

and R is CH=CH,

phenylene, biphenylene, naphthylene or (CH where c is an integer of from 0 to 8.

8. The modified polymer of claim 7 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

9. The modified polymer of claim 7 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

10. The modified polymer of claim 9 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

11. The modified polymer of claim 7 wherein said phenoplast comprises phenol condensed with formaldehyde.

12. The modified polymer of claim 11 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

13. The modified polymer of claim 1 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide, or p-aminobenzoylhydrazide.

14. The modified polymer of claim 13 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

15. The modified polymer of claim 13 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

16. The modified polymer of claim 15 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

17. The modified polymer of claim 13 wherein said phenoplast comprises phenol condensed with formaldehyde.

18. The modified polymer of claim 17 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

19. A rapid curing adhesive composition comprising a. an acyl hydrazide-modified condensation polymer comprising the reaction product of a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula wherein a and b are integers of from 0 to 8 and the sum ofa and b is from 0 to 12; x is 0 to l; R is CH=CH,

O, S, phenylene, biphenylene, naphthylene,

OH H o. c JON Ha ONz and R is NH N l-l or o bmm;

and

b. a curing agent reactable with said modified condensation polymer to form an insoluble, infusible polymer.

20. The composition of claim 19 wherein said curing agent comprises an alkylene donating compound, a diisocyanate, an epoxide or an epoxide-aldehyde mixture.

21. The composition of claim 19 wherein said curing agent comprises an aldehyde.

22. The composition of claim 19 wherein said curing agent comprises formaldehyde.

23. The composition of claim 19 wherein the amount of curing agent is from 0.05 to 2.0 parts by weight per part by weight of said modified condensation polymer.

24. The composition of claim 19 wherein said phenoplast comprises phenol condensed with formaldehyde.

25. The composition of claim 24 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminoben- Zoylhydrazide.

26. The composition of claim 19 wherein said acyl hydrazide is selected from those of the formula 0 H!N2 R7R1 wherein R is Nl-l N l-l or lN Ha;

and R is CH=Cl-l,

CH2 .i

phenylene, biphenylene, naphthylene, or (Cl-l where c is an integer of from 0 to 8.

27. The composition of claim 26 wherein said curing agent is an alkylene donating compound.

28. The composition of claim 26 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

29. The composition of claim 28 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.

30. A process for the preparation of a rapid curing adhesive composition comprising blending together a. an acyl hydrazide-modified condensation polymer comprising the reaction product of a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula (II) H.N.c tcH, R).- cHnwR.

wherein a and b are integers of from 0 to 8 and the sum ofa and b is from 0 to 12; x is 0 or i; R is CH=CH--, i 3

O, S, phenylene, biphenylene, naphthylene,

and R is NH N l-l or ii CNzHal and b. a curing agent reactable with said modified condensation polymer to form an insoluble, infusible polymer.

31. The process of claim 30 wherein said curing agent comprises an alkylene donating compound, a diisocyanate, an epoxide or an epoxide-aldehyde mixture.

32. The process of claim 30 wherein said curing agent comprises an aldehyde.

33. The process of claim 30 wherein said curing agent comprises formaldehyde.

34. The process of claim 30 wherein the amount of curing agent is from 0.05 to 2.0 parts by weight per part by weight of said modified condensation polymer.

35. The process of claim 30 wherein said phenoplast comprises phenol condensed with formaldehyde.

36. The process of claim 35 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.

37. The process of claim wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

38. The process of claim 37 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.

39. A process for producing a modified condensation polymer comprising reacting a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula wherein a and b are integers of from 0 to 8 and the sum ofa and b is from 0 to 12; x is 0 or i; R is CH=Cl-l,

O, S, phenylene, biphenylene, naphthylene,

and R, is Nl-l N H or O iENI SZ said modified polymer being further reactable with a curing agent to form an insoluble, infusible polymer.

40. The modified polymer of claim 39 wherein from 0.1 to 1.0 parts by weight of said acyl hydrazide is reacted with l part by weight of said phenoplast.

41. The process of claim 39 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.

42. The process of claim 41 wherein from 0.1 to 1.0

parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

43. The process of claim 41 wherein said acyl hydrazide is selected from those of the formula wherein R is NH,, N ll or z ai and R is ---CH=Cl-l,

' CH. I] c phenylene, biphenylene, naphthylene or (CH where c is an integer of from 0 to 8.

44. The process of claim 43 wherein from 0.] to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.

45. The process of claim 41 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide, or p-aminobenzoylhydrazide.

46. The process of claim 45 wherein from 0.] to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast. 

2. The modified polymer of claim 1 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 3. The modified polymer of claim 1 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.
 4. The modified polymer of claim 3 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 5. The modified polymer of claim 1 wherein said phenoplast comprises phenol condensed with formaldehyde.
 6. The modified polymer of claim 5 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 7. The modified polymer of claim 1 wherein said acyl hydrazide is selected from those of the formula
 8. The modified polymer of claim 7 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 9. The modified polymer of claim 7 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.
 10. The modified polymer of claim 9 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 11. The modified polymer of claim 7 wherein said phenoplast comprises phenol condensed with formaldehyde.
 12. The modified polymer of claim 11 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 13. The modified polymer of claim 1 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide, or p-aminobenzoylhydrazide.
 14. The modified polymer of claim 13 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 15. The modified polymer of claim 13 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.
 16. The modified polymer of claim 15 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 17. The modified polymer of claim 13 wherein said phenoplast comprises phenol condensed with formaldehyde.
 18. The modified polymer of claim 17 wherein from 0.05 to 2.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 19. A rapid curing adhesive composition comprising a. an acyl hydrazide-modified condensation polymer comprising the reaction product of a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula
 20. The composition of claim 19 wherein said curing agent comprises an alkylene donating compound, a diisocyanate, an epoxide or an epoxide-aldehyde mixture.
 21. The composition of claim 19 wherein said curing agent comprises an aldehyde.
 22. The composition of claim 19 wherein said curing agent comprises formaldehyde.
 23. The composition of claim 19 wherein the amount of curing agent is from 0.05 to 2.0 parts by weight per part by weight of said modified condensation polymer.
 24. The composition of claim 19 wherein said phenoplast comprises phenol condensed with formaldehyde.
 25. The composition of claim 24 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.
 26. The composition of claim 19 wherein said acyl hydrazide is selected from those of the formula
 27. The composition of claim 26 wherein said curing agent is an alkylene donating compound.
 28. The composition of claim 26 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.
 29. The composition of claim 28 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.
 30. A process for the preparation of a rapid curing adhesive composition comprising blending together a. an acyl hydrazide-modified condensation polymer comprising the reaction product of a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula
 31. The process of claim 30 wherein said curing agent comprises an alkylene donating compound, a diisocyanate, an epoxide or an epoxide-aldehyde mixture.
 32. The process of claim 30 wherein said curing agent comprises an aldehyde.
 33. The process of claim 30 wherein said curing agent comprises formaldehyde.
 34. The process of claim 30 wherein the amount of curing agent is from 0.05 to 2.0 parts by weight per part by weight of said modified condensation polymer.
 35. The process of claim 30 wherein said phenoplast comprises phenol condensed with formaldehyde.
 36. The process of claim 35 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.
 37. The process of claim 20 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, Phenol-resorcinol or resorcinol.
 38. The process of claim 37 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide or p-aminobenzoylhydrazide.
 39. A process for producing a modified condensation polymer comprising reacting a phenoplast containing reactive alkylol groups with an acyl hydrazide of the formula
 40. The modified polymer of claim 39 wherein from 0.1 to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 41. The process of claim 39 wherein said phenoplast is one comprising formaldehyde condensed with phenol, cresol, xylenol, phenol-resorcinol or resorcinol.
 42. The process of claim 41 wherein from 0.1 to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 43. The process of claim 41 wherein said acyl hydrazide is selected from those of the formula
 44. The process of claim 43 wherein from 0.1 to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast.
 45. The process of claim 41 wherein said acyl hydrazide is adipic dihydrazide, glutaric dihydrazide, sebacic dihydrazide, carbohydrazide, or p-aminobenzoylhydrazide.
 46. The process of claim 45 wherein from 0.1 to 1.0 parts by weight of said acyl hydrazide is reacted with 1 part by weight of said phenoplast. 